It is known in the industry that a golf club head joined to a shaft can transmit vibrational energy up the shaft to the player when the club head strikes a ball. These vibrations can be distracting to players as well as effecting the accuracy of the strike. Various vibration dampers have been proposed to eliminate this vibrational effect on the player.
U.S. Pat. No. 5,277,423 issued to Artus discloses a rigid tubular sleeve made of a visco-elastic material having a predetermined thickness and slidably connected to the shaft. The sleeve on the shaft serves as a vibration damping device by absorbing the energy released during the strike of a ball and converting it into heat.
Other means to dampen the vibrational energy of a golf club is to incorporate the visco-elastic material directly adjacent the surface of the club head wherein the damping material is located closer to the source of vibration. U.S. Pat. No. 5,290,036 issued to Fenton et al. discloses such a iron golf club wherein a vibration dampening material is set in the back cavity of the iron head. A problem that can be encountered with this damping location is that the damping material could also dissipate the energy of the striking ball and thereby diminish the efficiency of the hit.
Additionally, it was known in the industry to provide a perimeter weighted iron golf club head having a rear cavity in an attempt to provide a golf club head that improves off-center hits. Such iron heads are configured to redistribute the weight on the head, or to provide a uniform striking surface to maximize the performance of an off-center hit as well as an on-center hit.
U.S. Pat. No. 5,046,733 issued to Antonious provides a peripheral or perimeter weighted iron golf club head having a second peripheral weight member adjacent the first peripheral weight member to maximize off-center hits of the ball.
U.S. Pat. No. 5,282,625 issued to Schmidt et al. discloses a reconfigured iron head that achieves lateral sweet spot enlargement by providing undercuts at the toe and heel that extend outwardly from the rear cavity.